How to hire a CTO in the UK, fractional or full time
Hiring a fractional CTO in the UK takes seven steps: write the gap down, set the budget from the published day-rate band, check fractional is the right shape, shortlist people who have held the seat at your stage, interview with the six questions below, agree the day-ninety markers in writing, and contract the days and the IR35 position. Most companies go from brief to signed contract in about two weeks. To skip the reading and meet people, hire a fractional CTO from the seat page.
UK day rates for the seat run £800 to £1,400. All eleven seats compared →
Fractional or full time: which CTO hire you need
A fractional CTO costs £800 to £1,400 a day, usually two days a week, which is £6,133 to £10,733 a month with no employer costs. A full-time CTO is paid a base of £115,000 to £185,000, plus employer costs, and a retained search adds 25 to 33 per cent of first-year earnings. Fractional fits two or three days of judgement; full time fits five days of leadership.
| Route | Cost basis | Time to start | Commitment | Best for |
|---|---|---|---|---|
| Fractional | £800 to £1,400 a day; £6,133 to £10,733 a month at two days | Met within days, starting in one to three weeks | One to three days a week, usually a month's notice | Owning the CTO decisions two or three days a week |
| Interim | £15,333 to £26,833 a month at 5 days | Weeks rather than months | Full time for a fixed term, typically 3 to 9 months | Cover for a departure, a transaction or a turnaround with an end date |
| Full-time search | A base of £115,000 to £185,000, plus 25 to 33 per cent of year one as the search fee | ten to fourteen weeks of search, then three to six months of notice | Permanent and employed, five days a week | A five-day seat that is certain to be permanent |
The full-time package is set out on the CTO salary page, and how a permanent search for the seat runs is on CTO executive search. The difference between the three routes is set out in full on fractional versus interim versus full-time, and hiring a full-time executive covers the permanent route.
Hiring a fractional CTO in seven steps
- Write the gap down. Name the two or three things a fractional CTO must own in the first quarter, and how many days a week that is. Describe what exists: the stack, who builds now (agency or in-house, and how many), and the specific thing that hurts. A brief that just says need a CTO reads like a co-founder search, and experienced operators skip those. Below ↓
- Set the budget from the published band. UK fractional CTO day rates run £800 to £1,400 in 2026. Two days a week is £6,133 to £10,733 a month, with no employer costs on top. Fractional CTO cost →
- Check fractional is the right shape. A fractional CTO is two or three days a week for a year or more. If the need is five days for six months, or the seat is a full-time job already, interim or permanent fits better. Below ↓
- Shortlist people who have held the seat at your stage. Read track records, not titles. The right operator has been the CTO at a company of your size and stage before, and says what happened there in numbers. Browse the bench →
- Interview with the six questions. Every question asks for something that happened. An operator who has held the seat answers from memory; one who has advised from the sidelines answers in the abstract. Below ↓
- Agree the day-ninety markers in writing. Put the day-ninety outcomes in the brief before they start. A written technical risk register: the three things most likely to hurt the business, each with a rough cost and either a scheduled fix or a deliberate, documented decision to accept it. Below ↓
- Contract the days, the notice period and the IR35 position. Fix the days a week, a notice period of a month, who owns the output, and the IR35 determination. Then set the start date and the first ninety-day review. IR35 for fractional executives →
What the seat covers is on the fractional CTO page. The rest of this page is the part that usually goes unwritten: the interview, day ninety, and when this hire is the wrong answer entirely.
Where to find a fractional CTO in the UK
Four routes work, and most companies use two of them at once. Whichever finds the person, the shortlist test is the same: they have held the seat at a company of your size and stage before.
- A platform or bench with the rate on the profile. The day rate is visible before the first call, which settles the budget conversation early. The UK fractional platforms, compared.
- A search against a written brief. Somebody else runs the longlist and the first interviews and puts a shortlist in front of you. How Operator Search works.
- Your investors, accountant or lawyer. They have seen fractional CTOs work at other companies and know which ones they would have back.
- Other founders. A CTO who has done it at a company like yours is usually two introductions away. Ask what they would hire them for again, not whether they were good.
Six questions to ask, and what a strong answer sounds like
Every question here asks for something that happened, not something they believe. An operator who has genuinely held the seat answers from memory; one who has advised from the sidelines answers in the abstract, and the difference is audible within a minute.
1. Tell me about a rebuild you talked a company out of. What did you do instead?
Listen for: The strong answer weighs the rewrite in months and money, names what shipped instead, and shows some affection for unglamorous incremental work. Someone whose proudest story is a year-long rewrite is telling you what they will do to your codebase.
2. Walk me through the last engineer you hired. Where did they come from, what did the process actually test, and are they still there?
Listen for: You want a real pipeline, a work-sample or pairing exercise rather than puzzle questions, honesty about salary, and ideally someone who stayed. A vague answer about having a great network means the hiring, which is often the real work, will land back on you.
3. Our agency says the next feature is three months. How do you check whether that is true?
Listen for: Good answers involve reading the code, breaking the scope down, and asking for a demo cadence so slippage shows early. Taking estimates on trust is weak; assuming bad faith by reflex is a different kind of weak.
4. First week with our codebase: what do you look at, and what do you deliberately ignore?
Listen for: Listen for deployment pipeline, test coverage, security basics, and where the single points of failure are, with style debates and framework preferences explicitly parked. Wanting a full formal audit before offering any judgement suggests a consultant's pace, not an operator's.
5. When did you last choose the boring technology, and when did you last deliberately not?
Listen for: The right instinct is boring by default with one well-argued exception they can defend in business terms. A history of adopting whatever was newest, at someone else's expense, is common in this market and worth catching here.
6. What is your working policy on AI coding tools for a small team like ours?
Listen for: A considered answer is specific about where the tools speed a team up and where they generate review burden and unowned code, and includes how they would police it. Both the dismissive answer and the breathless one suggest they have not run a team with these tools in it recently.
Red flags
- They recommend a rewrite before reading the code or asking what actually breaks the business today. The diagnosis arrived before the patient.
- The first conversation is about their preferred stack rather than your product, your customers, and who maintains the system after they leave.
- They cannot name an engineer they hired or grew who is still at a previous company. A trail of teams that dissolved on their exit means they were the system, and you will inherit the same dependency.
- They angle to write the code themselves. A fractional CTO doing hands-on build at up to £1,400 a day is doing a £500-a-day contractor's work at the judgement rate, and the judgement work is not getting done.
What day ninety should look like
Agree these before they start, in writing, in the brief. A fractional engagement without a ninety-day marker drifts into a retainer nobody remembers the point of.
- A written technical risk register: the three things most likely to hurt the business, each with a rough cost and either a scheduled fix or a deliberate, documented decision to accept it.
- Visible delivery discipline: releases on a stated cadence, and an estimate for the roadmap item you care about with its assumptions written down, so you can hold someone to it.
- The build question settled for your setup: either a hiring plan with a live candidate pipeline, or a documented review of the agency with scope and cost renegotiated. One of the two, done, not discussed.
When a fractional CTO is the wrong answer
- There is no product yet and no engineers. What you need is people who write code, whether senior engineers or a good agency. A day a week of oversight with nothing to oversee is pure overhead.
- You already have strong senior engineers and the real gap is deciding what to build. That is the product seat. Adding another technologist above good ones creates friction, not direction.
- Production is failing daily: outages, data loss, customers leaving. That is a full-time interim engagement until the fire is out. Two days a week arrives on Tuesday to find Monday's decisions already made.
If one of those is you, say so in a brief anyway and we will tell you straight. Sometimes the honest answer is interim or full-time.
What to put in a fractional CTO brief
- Describe what exists: the stack, who builds now (agency or in-house, and how many), and the specific thing that hurts. A brief that just says need a CTO reads like a co-founder search, and experienced operators skip those.
- State decision rights and days together: whether they can change suppliers, pause roadmap items and set the hiring bar, and how many days a week you expect. Architecture authority without roadmap authority is a brief good CTOs turn down.
- The thing founders forget to say: whether you are quietly hoping this turns into a full-time or co-founder role, and whether equity is on the table. Operators can tell when a fractional brief is really a co-founder search, and the undisclosed version wastes everyone's time. If that is the hope, write it down.
What the contract should cover
General guidance rather than legal advice: have the engagement letter read by somebody who acts for you. These are the clauses that cause the arguments when they are missing.
- The days. How many a week or a month, whether they roll over, and the day rate or monthly figure that pays for them.
- Notice. A month either way is the usual term, long enough to hand over and short enough that neither side is trapped.
- Intellectual property. Who owns the models, documents and code the CTO produces. It should be the company, said in writing, because without a clause it may not be.
- IR35. Whether the engagement is inside or outside, who made the determination, and the reasons. IR35 for fractional executives explains who carries the decision.
The rest, from confidentiality to conversion terms, is in what a fractional executive contract should say.
Common questions about hiring a fractional CTO
How quickly can a company hire a fractional CTO?
Faster than any other way of filling the seat. A request to a fractional CTO on the bench is accepted or declined within three days, and a brief to Operator Search returns a shortlist in five business days. A permanent CTO search runs ten to fourteen weeks to an accepted offer and then a notice period of three to six months, which is why fractional cover is the normal bridge.
How many days a week should a fractional CTO be hired for?
Two is the most common arrangement and one to three is the working range. Below a day a week nobody can own a function; above three the seat has usually become a full-time one and the honest conversation is about converting. Start at the lower end and add a day when decisions begin queueing for the CTO's days.
What is the monthly cost of a fractional CTO two days a week?
At the 2026 UK band of £800 to £1,400 a day, two days a week over 46 working weeks comes to £6,133 to £10,733 a month, invoiced by the operator's own company with no employer National Insurance, pension or recruitment fee on top. Higher end for regulated sectors, AI systems and technical due diligence.
Can a fractional CTO later become the full-time CTO?
Yes, and it is one of the better routes to a permanent hire because both sides have had months of working interview. Raise the possibility early so the operator can plan their other clients, agree a start date around their notice to those clients, and check the engagement letter for any conversion terms before the conversation.
What should a brief for a fractional CTO say?
The three outcomes the seat owns in the first ninety days, the days a week and whether on site matters, who the CTO reports to and who reports to them, the systems and data they will inherit, and the budget as a day rate or a monthly figure. A brief that lists tasks rather than outcomes attracts people who want a to-do list, and the fractional CTOs worth hiring decline it.
When should a company hire a full-time CTO?
When the seat needs five days, not two: a team of leaders to run, a transaction to carry, or a board that wants the CTO in every room. A full-time CTO in a UK company of twenty to two hundred people is paid a base of £115,000 to £185,000 in 2026, and a retained search adds 25 to 33 per cent of first-year earnings. Until the days are queueing, fractional is the cheaper test.
How long does it take to hire a CTO, fractional or full time?
A fractional CTO is usually met within days and starts in one to three weeks: Operator Search returns a shortlist in 5 business days, and a request on the bench is answered within three. A permanent CTO takes ten to fourteen weeks of search to an accepted offer, then a notice period of three to six months, so a first day is usually six months or more away.
How do I find a part-time CTO?
Four routes work in the UK: a fractional platform or bench where the day rate is published before you speak to anybody, a search run against a written brief, a referral from an investor, accountant or another founder, and the CTO's own network of former colleagues. Whichever route, shortlist people who have held the seat at your stage, and agree the days, the notice period and the IR35 position in writing.
Two ways in
Browse verified fractional CTOs on the bench and book direct, or brief Operator Search and we run the interviews above for you.